Hello all, this isn't the first post here that I was hoping of!
After some fairly heavy work the 3.9L EFI in one of our Range Rovers finally did the head gaskets. It had been missing on startup for a long while before this.
Anyway, off came the heads and both went away to be pressure tested and skimmed (faces were high down their length in the middle) before rebuilding the engine with a composite gasket kit.
After rebuild the engine fired up better than it ever has done before so the heads definitely needed doing.
The problem is that it heats up in under a mile when already warm. It will idle all day with the cap off trying to get air out although it does glug and bubble a bit.
Top hose / thermostat never seem to have more than a tiny trickle in the bottom.
Assuming the block isn't faulty as well, what's the trick getting air out?!
Thanks.
3.9 Stubborn Airlock?
Moderator: phpBB2 - Administrators
Hi welcome, fortunatly you have a problem that is at least cheep to fix 
The way I dealt with this on my RRs was basically down to persistance others may have methods that involve a little less time but here goes
1/ take the filler bung out, switch the heater on full.
2/ get some hot water from the tap in a pop bottle/ jug with a narow spout, you need to get water into the filler without a funnel that goes below the surface of the coolant
3/ fill the cooling system as far as you can with antifreeze mix about 25 richer than you want to end up with
4/ start the engine and warm it up, as it warms blip the throttle from time to time, if the level drops, fill it up again straight away.
5/ as it warms up feel the hoses, if there is a cooler patch on one squeeze the hoase there repeatedly up until it feels warm, you are squeezing out the air at that point, when the air makes it's way to the filler top up the cooling system.
6/ repeat 5 several times going around the system as air pockets will work their around the cooling system and get stuck in the same places on their way to the filler. blip the throttle several times as you go.
7/ don't let it get too hot, if it does then stop and let it cool, however you need it hot enough for the thermostat open to get all the air out.
8/ When you have done this and think you have all the air out take it out for a very short spin, but as if it looks as if you still have air in the system stop and let it cool then take it home and do the procedure again.
9/ if this doesn't work then you may have the heater full of air, take the hoses off the heater and fill it directly refit the hoses again and purge the system again.
10/ if this is still unsuccesfull then you have a more serious issue like a non seated head gasket or a dropped liner, you will need to check this by gatting the coolent checked for hydrocarbon residue, fix it and go to 1
Best regards
Mike
The way I dealt with this on my RRs was basically down to persistance others may have methods that involve a little less time but here goes
1/ take the filler bung out, switch the heater on full.
2/ get some hot water from the tap in a pop bottle/ jug with a narow spout, you need to get water into the filler without a funnel that goes below the surface of the coolant
3/ fill the cooling system as far as you can with antifreeze mix about 25 richer than you want to end up with
4/ start the engine and warm it up, as it warms blip the throttle from time to time, if the level drops, fill it up again straight away.
5/ as it warms up feel the hoses, if there is a cooler patch on one squeeze the hoase there repeatedly up until it feels warm, you are squeezing out the air at that point, when the air makes it's way to the filler top up the cooling system.
6/ repeat 5 several times going around the system as air pockets will work their around the cooling system and get stuck in the same places on their way to the filler. blip the throttle several times as you go.
7/ don't let it get too hot, if it does then stop and let it cool, however you need it hot enough for the thermostat open to get all the air out.
8/ When you have done this and think you have all the air out take it out for a very short spin, but as if it looks as if you still have air in the system stop and let it cool then take it home and do the procedure again.
9/ if this doesn't work then you may have the heater full of air, take the hoses off the heater and fill it directly refit the hoses again and purge the system again.
10/ if this is still unsuccesfull then you have a more serious issue like a non seated head gasket or a dropped liner, you will need to check this by gatting the coolent checked for hydrocarbon residue, fix it and go to 1
Best regards
Mike
poppet valves rule!
